One-transistor dynamic random access memory—Dr. Dennard's invention of DRAM, most often called RAM, was a core development in today's computer industry and is one of the most commonly used devices in the world. RAM is the system which has supplied the memory needs of all computers since the early 1970s. Before his invention, computers were too large and heavy to be installed in private homes or desk tops. In fact, they required separate storage space and air conditioning to cool them. The device was patented in 1968 by Dennard who was a computer engineer with IBM. Since 1963, he has been a fellow at IBM's Thomas Watson Research Center in Yorktown Heights, New York. (1997)